Cartridge

ABSTRACT

A cartridge arrangement comprises a frangible portion and a guide tube. The frangible portion being substantially housed within the guide tube with an end of the frangible portion being sealed by a clip. A cap attaches to an end of the guide tube by a screw thread. Unscrewing of the cap urges arms, having a portion seated behind the clip, away from the guide tube thereby opening the frangible portion.

FIELD OF THE INVENTION

This invention relates to a cartridge.

BACKGROUND TO THE INVENTION

Cartridges comprising a bag like flexible membrane housed within a rigidbody are known to those skilled in the art, see for example EuropeanPatent No. 0 754 633 and European Patent Application No. 04 714 857.2.

Typically, such a cartridge is used in standard caulking gun. Thisallows the contents of the cartridge to be applied in a controlledmanner.

The closure of the flexible membrane in order to retain the cartridgescontents within it represents a particular difficulty. European PatentApplication No. 04 714 857.2 discloses an arrangement where a staple iswound around an open end of a flexible membrane to close the membrane.The action of caulking gun piston on an opposite end of the membraneforces the membrane's contents past the staple, thereby opening themembrane.

Such an arrangement has a number of disadvantages. Firstly, it isnecessary to provide a weakened staple compared to conventional staplearrangements. This weakening of the staple decreases the resistance ofthe closure to leakage of the membrane's contents.

Also, the reliance on the indirect pressure of the piston to force thestaple open results in a low reliability of opening.

European Patent No. 0 754 633 discloses an arrangement whereby a lengthof membrane is pulled through a neck of a rigid body of a cartridge andhas a clip attached to it. The clip is sufficiently wide to prevent thepassage of the membrane back through the neck.

This arrangement requires the cutting of the membrane in order to allowthe membrane's contents to flow out of the cartridge.

SUMMARY OF THE INVENTION

According to a first aspect of the present invention there is provided acartridge arrangement comprising a frangible portion, the frangibleportion being substantially housed within a guide tube, an end of thefrangible portion being sealed by sealing means, characterised byengagement means arranged to engage the sealing means such that motionof the engagement means away from the guide tube urges the sealing meansaway from the frangible portion.

This arrangement simplifies the opening of a cartridge by reducing thenumber of steps requires to open a cartridge, preferably to a singlestep.

The use of engagement means allows the use of a non-weakened sealingmeans. This reduces leakage of the contents of the cartridge.

Additionally, the engagement means provide a reliable means of openingthe internal portion of the cartridge. This provides increasedreliability of opening of the cartridge over prior art arrangements dueto the direct linkage of the engagement means with the sealing means.

Such an arrangement does not require the cutting of the internal portionof the cartridge to release its contents. This increases the ease ofoperation of the cartridge over prior art arrangements.

The engagement means may comprise a resilient member having at least oneprojection arranged to abut the sealing means. The engagement means maybe fabricated from a plastics material.

The engagement means may comprise a cap arranged to attach to an end ofthe guide tube. The cap may be arranged to engage the guide tube bymeans of a screw thread.

The engagement means may comprise a locking plate located between an endof the cap and a head of the engagement means.

The engagement means may comprise arms having a portion shaped such thatthey are complementarily curved to the curvature of a section of thecap.

This allows the rotation of the cap when screwing and unscrewing the capwithout imparting rotational motion to the arms. This reduces the chanceof slippage of the arms over the cartridge.

A portion of the engagement means may be arranged to locate within aneck of the guide tube. Alternatively, a portion of the engagement meansmay be arranged to locate within a body of the guide tube.

These two alternative arrangements allow for the use the invention withpartially full and full cartridges

The sealing means may comprise a staple or a clip.

BRIEF DESCRIPTION OF THE DRAWING

The present invention will now be described, by way of example only,with reference to the accompanying drawing, in which:

FIG. 1 is a cross section of a dispensing device comprising a cartridgearrangement according to the present invention.

DESCRIPTION OF PREFERRED EMBODIMENTS

Referring now to FIG. 1, a dispensing device 10 comprises a frangiblecartridge 12, a guide tube 14 and a cap 16.

The frangible cartridge 12 comprises two compartments 18, 20. Eachcompartment 18,20 contains a respective component to be dispensed. Thecomponents are typically fluids or semi-solid components. A free end 22of the cartridge 12 is sealed with a closure 24, typically a ring stapleor a clip. Typically, the cartridge 12 is fabricated from a flexible,pliable material, usually a plastics material.

The guide tube 14 comprises a hollow cylindrical body 26 and a nozzleadaptor 28. The nozzle adaptor 28 comprises a central hollow cylindricalbore 30, a shoulder portion 32 and a neck 34. The exterior of the neck34 has a thread 36 provided over a region of its external surface.

The guide tube 14 receives the cartridge 12 such that the free end 22passes into the neck 34. In some embodiments the free end 22 will passthrough the neck 34 such that the closure locates externally of the neck34.

The cap 16 comprises a cylindrical body portion 36 and an inwardlytapering, open ended frustoconical head section 38. The body portion 36is comprises an internal thread 40, which is complementarily threaded tothe external thread 36 of the neck 34.

A jaw arrangement 42 that is locatable within the cap 16 comprises apair of opposed arms 44 a,b. Each of the arms 44 a,b comprises a flaredhead 46, a waist 48, a curved shoulder 50, a leg 52 and a foot 54.

The arms 44 a,b are positioned such that the respective feet 54 locatebehind and, in a preferred embodiment, abut the closure 24 remote fromthe free end 22. The cap 16 threads on to the neck 34 such that therespective flared heads 46 project through the open end of the headsection 38, and reside externally of the cap 16.

The respective waists 48 pass partially through the opening of the headsection 38, with the remainder residing in the opening. The shoulders 50are chamfered such that they abut an internal surface of the headsection 38. The legs 52 project towards the open end of the body portion36, forming an L-shape with a terminal end face of the shoulder 50. Thefoot 54 projects inwardly towards the central axis of the cap 16.

A C-shaped plate 56 is fitted around the waists 48 between the heads 46and the head section 38 of the cap 16. Typically, the plate 56 is shapedsuch that it fits around the waists 48 snugly and abuts both undersidesof the heads 46 and an outer annular surface of the head section 38.

In order to open the cartridge a user unscrews the cap 16 from the neck34. Usually, the shoulders 50 are shaped such that they arecomplementarily curved to the curvature of the internal surface of thehead section 38. This allows the cap 16 to be unscrewed without rotationof the arm 44 a,b. As the cap 16 is unscrewed the plate 56 engages theheads 46 of the arms 44 a,b and urges them away from the guide tube 14.As the feet 54 engage the closure 24 the closure 24 moves in sympathywith the arms 44 a,b and slides over the cartridge 12 towards its freeend 22.

As the unscrewing of the cap 16 progresses the closure 24 will pass overthe free end 22 of the cartridge 12. This results in the opening of thecartridge 12.

It will be appreciated that although described with reference to acompartment cartridge the present invention is applicable to singlecompartment cartridges and also cartridges having more than twocompartments.

It will be further appreciated that although described with reference toan arrangement wherein the closure is located within the neck of theguide tube the closure may be located within the body of the guide tube.In such an arrangement the arms of the jaw arrangement must be longerthan in the present embodiment.

In a further embodiment, not shown, an L-shaped catch is inserted intothe neck of the guide tube, the short arm of which engages behind theclosure. The closure can then be levered free of the cartridge, therebyopening the cartridge. It will be appreciated that the catch may beinserted into the neck manually, or it may depend from the cap.

1. A cartridge arrangement comprising: a frangible portion, thefrangible portion being substantially housed within a guide tube, an endof the frangible portion being sealed by sealing means and an engagementmeans arranged to engage the sealing means such that motion of theengagement means away from the guide tube urges the sealing means awayfrom the frangible portion.
 2. A cartridge arrangement according toclaim 1, wherein the engagement means comprises a resilient memberhaving at least one projection arranged to abut the sealing means.
 3. Acartridge arrangement according to claim 1, wherein the engagement meansis fabricated from a plastics material.
 4. A cartridge arrangementaccording to claim 1, wherein the engagement means comprises a caparranged to attach to an end of the guide tube.
 5. A cartridgearrangement according to claim 4, wherein the cap is arranged to engagethe guide tube by means of a screw thread.
 6. A cartridge arrangementaccording to claim 5, wherein unscrewing of the cap when engaged isarranged to urge the sealing means away from the guide tube.
 7. Acartridge arrangement according to claim 4, wherein the engagement meanscomprises a locking plate located between an end of the cap and a headof the engagement means.
 8. A cartridge arrangement according to claim1, wherein the engagement means comprises arms having a portion shapedsuch that they are complementarily curved to the curvature of a sectionof the cap.
 9. A cartridge arrangement according to claim 1 wherein aportion of the engagement means is arranged to locate within a neck ofthe guide tube.
 10. A cartridge arrangement according to claim 1 whereina portion of the engagement means is arranged to locate within a body ofthe guide tube.
 11. A cartridge arrangement according to claim 1 whereinthe sealing means comprises a staple or a clip.
 12. A cartridgearrangement comprising: a frangible portion, the frangible portion beingsubstantially housed within a guide tube, an end of the frangibleportion being sealed by a clip, and a cap arranged to attach to an endof the guide tube by a screw thread wherein unscrewing of the cap whenengaged urges arms, having a portion seated behind the clip, away fromthe guide tube thereby opening the frangible portion.
 13. A cartridgearrangement comprising: a frangible portion, the frangible portion beingsubstantially housed within a guide tube, an end of the frangibleportion being sealed by a sealing device, and a plastic cap arranged toattach to an end of the guide tube by a screw thread wherein unscrewingof the sealing device when engaged urges one or more arms, each of theone or more arms having a portion seated behind the sealing device, awayfrom the guide tube thereby opening the frangible portion.